/*  mbed Microcontroller Library
    Copyright (c) 2006-2013 ARM Limited

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/
#ifndef MBED_ANALOGOUT_H
#define MBED_ANALOGOUT_H

#include "platform.h"

#if DEVICE_ANALOGOUT

#include "analogout_api.h"

namespace mbed {

    /** An analog output, used for setting the voltage on a pin

        Example:
        @code
        // Make a sawtooth output

        #include "mbed.h"

        AnalogOut tri(p18);
        int main() {
           while(1) {
               tri = tri + 0.01;
               wait_us(1);
               if(tri == 1) {
                   tri = 0;
               }
           }
        }
        @endcode
    */
    class AnalogOut {

      public:

        /** Create an AnalogOut connected to the specified pin

            @param AnalogOut pin to connect to (18)
        */
        AnalogOut(PinName pin) {
            analogout_init(&_dac, pin);
        }

        /** Set the output voltage, specified as a percentage (float)

            @param value A floating-point value representing the output voltage,
              specified as a percentage. The value should lie between
              0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%).
              Values outside this range will be saturated to 0.0f or 1.0f.
        */
        void write(float value) {
            analogout_write(&_dac, value);
        }

        /** Set the output voltage, represented as an unsigned short in the range [0x0, 0xFFFF]

            @param value 16-bit unsigned short representing the output voltage,
                      normalised to a 16-bit value (0x0000 = 0v, 0xFFFF = 3.3v)
        */
        void write_u16(unsigned short value) {
            analogout_write_u16(&_dac, value);
        }

        /** Return the current output voltage setting, measured as a percentage (float)

            @returns
              A floating-point value representing the current voltage being output on the pin,
              measured as a percentage. The returned value will lie between
              0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%).

            @note
              This value may not match exactly the value set by a previous write().
        */
        float read() {
            return analogout_read(&_dac);
        }

        #ifdef MBED_OPERATORS
        /** An operator shorthand for write()
        */
        AnalogOut& operator= (float percent) {
            write(percent);
            return *this;
        }

        AnalogOut& operator= (AnalogOut& rhs) {
            write(rhs.read());
            return *this;
        }

        /** An operator shorthand for read()
        */
        operator float() {
            return read();
        }
        #endif

      protected:
        dac_t _dac;
    };

} // namespace mbed

#endif

#endif
